ANALYSIS OF MULTI STOREY BUILDING BY USING STEEL BRACING

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ANALYSIS OF MULTI STOREY BUILDING BY USING STEEL BRACING

Prof. Shashikant Manekari

1

_{, Mr.Sagar Dhotre}

2

_{, Miss.Aparana Sathe}

3

_{, Mr. Ganesh Havile}

4

_,

Mr.Aniket Rathod

5

_{, Mr.Navin Gajul}

6

1

_{Assistant Professor, Department of Civil Engineering, V.V.P.I.E.T, Solapur, Maharashtra, India.}

2,3,4,5,&6

_{U.G. Student, Department of Civil Engineering, V.V.P.I.E.T, Solapur, Maharashtra, India.}

---***---Abstract : The most of steel structure are failed in latral

loads. Different bracing systems are different seismic responses. Steel bracing system have both practical and economical advantage. The applications of Steel bracing is quicker to execute. The aim of the study of a seismic response of building is to style and build a structure during which the damage to the structures and its structures component by earthquake may be a minimised. The paper aims to was the review of study of study of an brased and brased multi-story steel building conducted by various authors within the post.

Key Words Steel frame, Bracing, Earthquake, seismic

1.INTRODUCTION 1.1 General

The huge strength of steel is of great advantage to steel structures. Pliant is important factor of steel structure. Great advantage of the steel is plasticity or ductility it means that when subjected to considerable force it will not suddenly crack like glass, but slowly bend out of shape. It allows steel structure to bend out of shape, or deform. Failure in steel frames isn’t sudden, a steel structure rarely collapses. Steel in most cases performs far better in earthquake than most other materials because ofthese properties. A soft story building is a multi-story building in which one or more floors have large unobstructed commercial spaces, windows, wide doors or other openings in places where a axialwall would nomally be required for stability as a matter of earthquake engineering design.

1.2 Types of bracings A) Diagonal bracing B) Cross bracing C) Zip type of bracing D) K type of bracing E) V Type of bracing

Fig.1.1 Types of bracings

2. MODELLING 1.PLAN

The analysis of G+5, G+10, G+15, and G+20 by using X and V bracing in steel structure in Staad Pro software. G+5, G+10, G+15, and G+20 is analysed with and without bracings. To find out maximum bending moment , Nodal displacement.

Fig. 2.1 Plan of building with x bracing

Fig. 2.2 Plan of building with v bracing 2. STEEL BRACINGS WITHOUT BRACINGS

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Selected plan area is rectangular size. The advantage of bracings system is completely small increasing in mass associated with retrofitting scheme.

3. STEEL BRACINGS WITH X BRACING

Fig 2.4 X braced G+10 Building

The bracing system is used in the case of Steel in clan and member with the cross section dimension 150×150×10 mm.

4. STEEL BUILDING WITH V BRACING

Fig 2.5 V braced multi-story stracture CASE 1

WHEN BRACINGS ARE PROVIDED AT THE NEED BE COMPLETELY THROUGHOUT THE STORY BOTH IN X AND V TYPE

Fig .3.7 V bracing in middle Bay CASE 2

WHEN THE BRACING SUPPORTED AT THE OUTER PERIPHERY CAL COLUMNS WITH A GAP OF ONE STOREY UN BRACED.

Fig.3.8 V bracing 2nd_postion CASE 3

WHEN BRACINGS ARE PROVIDED AT THE OUTER PERIPHERYCAL COLUMN WITH ALTERNATE FASHION

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4. RESULTS

The following results are based on their case study the following result shows the nodal displacement acting on a X Braced and V Braced G+5 building.

Table -1: Nodal displacement vs Different Storey level STOREY LEVEL UNBRACED X BRACED V BRACED

GF 0 0 0 1 0.061 0.028 0.014 2 0.111 0.145 0.016 3 0.18 0.155 0.022 4 0.231 0.19 0.428 5 0.318 0.286 0.723

Fig. 4.1 Graph showing nodal displacement vs different story level

Table 2 Bending moment with different bracing type BRACING TYPE BRACING MOMENT

UNBRACED 22.965 X BRACED 33.328 V BRACED 24.325

Fig. 4.2 Graphical view of Bending moment

The following results are based on their case study the following result shows the nodal displacement acting on a X Braced and V Braced G+10 building.

Table 4.3 Nodal displacement VS Storey level G+10 STOREY

LEVEL UNBRACED X BRACED V BRACED GF 0.764 25.008 23.862 1 0.689 24.126 21.018 2 0.694 22.216 20.203 3 0.808 21.919 15.149 4 0.741 18.163 14.256 5 0.679 16.315 12.926 6 0.429 13.916 7.035 7 0.329 9.216 4.108 8 0.126 7.073 3.481 9 0.106 6.231 2.32 10 0.103 5.412 1.235

Fig.4.3 Graphical view of nodal displacement vs Storey level

Table 4.4 Bending moment with types of bracings

BRACING TYPE BRACING MOMENT

UNBRACED 12.41 X BRACED 42.928 V BRACED 24.196 0 5 10 15 1 2 3 4 5 6 N o d al d isp lac e m e n t Storey level

Nodel Displacement

STORY LEVEL UNBRACE D X BRACED V BRACED 0 10 20 30 40

UNBRACED X BRACED V BRACED

BRACING MOMENT

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Fig. 4.4 Graphical view of bending moment Table 4.5 Nodal displacement VS Storey level STOREY

LEVEL UNBRACED X BRACED V BRACED

GF 0 0 0 1 0.094 0.156 0.187 2 0.173 0.279 0.245 3 0.269 0.413 0.336 4 0.349 0.61 0.483 5 0.425 0.651 312 6 0.492 0.711 0.678 7 0.549 0.756 0.731 8 0.597 0.753 0.818 9 0.492 0.82 0.821 10 0.483 0.896 0.832 11 0.482 0.921 0.869 12 0.357 0.935 0.901 13 0.235 0.943 0.912 14 0.226 0.956 0.923 15 0.213 0.962 0.935

Table 4.6 Bending moment with types of bracings BRACING TYPE BRACING MOMENT UNBRACED 89.24

X BRACED 54.308 V BRACED 24.596

Fig. 4.6 Graphical view of Bending moment Table 4.7 Nodal displacement VS Storey level STOREY

LEVEL UNBRACED X BRACED V BRACED

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Table 4.8 Bending moment with types of bracings

BRACING TYPE BRACING MOMENT

UNBRACED 8.23 X BRACED 13.823 V BRACED 12.855

Fig. 4.8 Graphical view of Bending moment

5. Conclusions

1) The efficiency of x bracing 1s maximum as By using X bracings and V bracings the lateral nodal displacements are reduced by 75% and 68% respectively compared to braced steel building structure.

2) Steel bracing using a back to back angle section reduced the deflection by 3.2% when compared to steel bracing of the same type of bracings system. 3) The axial loads on the peripheral columns

increase racings. The axial loads increase in their value by 33.65% using X steel bracings.

4) The axial load on the interior columns increased by 15% irrespective of kind and type of bracings used.

5) The column moments on the peripheral columns have reduced bracing by using 15% but the column moments on the interior columns have drastically reduced by 74.31%.

6) Bending moment in column decreases from unbraced to braced system.

6. REFERENCESS

[1]. Reference 1Chopra A.K., (1997) “Dynamics of Structure”, 2nd Ed., Prentice Hall of India Pvt. Ltd., New Delhi.

[2]. Mario Paz, (1987) “Structural Dynamics”, 2nd Ed., CBS Publishers.

[3]. V.N. Vazirani and M.M. Ratawani, (1985) “Analysis of Structures”, 10th Ed., Khanna Publishers.

[3]. I.S. 456-1993, Indian standard code of practice fr plain And reinforced concrete (fourth revision), Bureau of Indian Standards, New Delhi.

[4]. I.S. 1893(Part 1)-2002, Criteria for earthquake resistant Design of structure, general provision and building, Bureau Of Indian standards, New Delhi.

[5]. I.S. 4326-2000, Indian standard code of practice for Earthquake resistant design and construction of buildings, Bureau of Indian standards, New Delhi.

[6]. I.S.13920: 1993, Indian standard code of practice for Ductile detailing of Reinforced concrete structure subjected To seismic forces, Bureau of Indian Standards, New Delhi.

[7]. I.S. 875 (part I and part II): 1987, Indian sandard code Of practice for design loads (other than earthquake) for Buildings and structures, Bureau of Indian standards, New Delhi.

[8]. A. R. Khaloo & M. Mahdi Mohseni, “Nonlinear Seismic Behaviour of RC Frames with RC Braces” Asian Journal of Civil Engineering, Vol. 9, No. 6 (2008).

[9]. A.A.Shish Ranka, Arathy Gopal, RahuL Jee, Earthquake Resistant Building Design Seminar Report”

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[11]. J.P. Desai, A.K. Jain and A.S. Arya, “Seismic response Of R.C. Braced Frames”, Computers and Structures Vol. 29, No. 4 (1987).

[12]. Mahmoud R. Maheri, R. Akbari, “seismic behaviour Factor, for steel x-braced and knee-braced rc buildings”, Engineering Structures, Volume 25, Issue 12, October 2003,

[13]. Yunfei H., Yufeng C., Chang, S., and Bainian H., “The Experimental Study of a Two-Bay Three Story Reinforced Concrete Frame Under Cyclic Loading”,Proceedings of the Eighth Symposium on Earthquake Engineering, Roorkee, India (1986).

[14]. L. Di Sarno, A.S. Elnashai, “Bracing systems for Seismic retrofitting of steel frames” (2008)

[15]. W. N. Deulkar et.al., “Buckling restrained braces for Vibration control of building structure” (2010)

BIOGRAPHIES

Name : Prof. Shashikant S. Manekari Qualification : M.E.(Structure) Assistant Professor at VVP IET Solapur

Name : Mr. Sagar k Dhotre Qualification ; B tech ( CIVIL) U.G Student at VVP IET Solapur

Name ; Miss. Aparana Sathe Qualification ; B tech ( CIVIL) U.G Student at VVP IET Solapur

Name ; Mr. Ganesh Havile Qualification ; B tech ( CIVIL) U.G Student at VVP IET Solapur

Name ; Mr. Aniket Rathod Qualification ; B tech ( CIVIL) U.G Student at VVP IET Solapur